Hello,

I'm trying to use the mri_glmfit function but keep running into the same error.

I am using the FSGD format and have set up my fsgd file according to the tutorial instructions:

" GroupDescriptorFile 1
Title mci_age_BNTchange
Class Male
Class Female
Variables        Age     BNTchange
Input   Subject1   Male    70   2
Input   Subject2   Female   75   -3
Input   Subject3   Female   72   0
etc."

Our .mat file states:

" 0 0 0 1" indicating that "BNTchange" is our variable of interest.

We are attempting to run a DOSS analysis.

The line of code I type into the terminal is:

" mri_glmfit --glmdir mci_age_bntchange_lh --y dv-visit2-lh.mgz --fgd mci_age_bntchange.fsgd doss --C mci_age_bntchange.mat"

This results in the following error:

"ERROR: matrix is illconditioned or badly scaled, condno = 1e+08"

We have tried runninf this off of different versions of Freesurfer (R302 and R305) and cannot figure out how to fix this error.

Any help would be appreciated!

Thanks!

- Lusineh Gharapetian